Improvement in sewing-machines



No. 27,594.. PATENTED MAR. 20, 1860.

L. W. LANGDON. SEWING MACHINE.

EEEEEEEEEEEEE PATENTED MAR. 20, 1860.

L. W. LANGDON. SEWING MACHINE.

2 SHEBTSSHBET 2.

lnventor.

Fig. 8.-

Witnesses.

' a Figure lis a perspbctive view of my machine;

- UNITE STATES- PATENT OFFI E;

L, w. LANGDON, or "NORTHAMPTON, MASSACHUSETTS, ASSIGNOR T0 HIM- v SELF, HTRAM W LLS, AND D. o. LI TLEFIELD, 0F SAME PLACE.

IMPROVEMENT INSEWING-IMACHINES;

-Specifieat1on 'forniii'ig mtruaeisrmem No'. 21,594, dated March 20, 1860. i

To all whom it may concern State of Massachusetts, have invented certain Improvements in SewingMachines, of which the following is afull, clear, and exact description, reference being had to the accompanying drawings, making part of this specification, in which'.

Fig. 2, a detached view of the shuttle-race and shuttle-driver; Fig. 3, an elevation of the driv-,

ing-shaft with its cranks and revolving take-up; Fig. 4, a detached view of the rock-shaft W,

, which operates the feed; Fig. 5,aview' ofthe inner plate of the revolving take-up Fig. 6, a de-' tached view of the'shuttle-driver; Fig. -7, a section through the shuttle-race, shuttle-driver, and shuttle; Fig. 8, details of the feeding-foot; Fig. 9, a section through the presser 'tbot; Fig.

10, a view of the back plate of the tension-regulator; Fig. 11, detail showing the operation of the hook T, which takes up the Slack of the g shuttle-thread.

7 The uniform motion obtained by the-use of a crank renders it far preferable to a 'cam for the purpose of driving the needle, as it can be run withmuch less friction, and consequently much more rapidly and with less power; but this very uniformity of motion renders it inapplicable to needle and shuttle sewing-machines, I

as it does not leave the needle sufficiently long beneath the cloth to allow the shuttle to pass through the loop.

,. Thefirst part of my invention has for its object to remedy this difiieulty; and'it -con'sists' in a peculiar revolving take-up" which is attached'to the driving-shaft, and operates independently of theneedle-bar, casts off the thread at the required moment to formthe .loop for the entrance of the shuttle, leaves the loop loose until the shuttle has passed through, andthenk' tightens up the stitch. When the needle-thread is thus controlled and the needle isdriven by 1 a crank, it becomes necessaryto tighten up the j stitch after the needle commences to descend and while the shuttle is upon its back traverse; but it is manifest that this could not be accomplished with a shuttle as ordinaily ar-" ranged, as upon the return of the shuttle the shuttle-tlu'ead is left slack, and would consequently be drawn through the cloth by-the needlethread.

To remedy this is the object of the. second part of my invention, which consists in keeping the shuttle-thread taut, during the return of the shuttle, by means of avibrating hooker other equivalent device that shall take the shuttle-thread after the shuttle has passed through the loop in the needle-thread and hold it distended until after the stitch is tightened up, the same device serving also to keep the Shuttle-thread out of the way of the needle as it descends and prevent it fronr 'ein entangledtherewith. Iam thus enabled to drive both the needle and the shuttle by means of cranks, and at the same time to allow the needle to recede for the formation of the loopbefore the shuttle advances.

The third part of my invention consists in a peculiar methodofoperatlngaSewing-machine feed having the four following motions; first, toward the cloth to engage therewith; second,

in advance to feed the cloth along; third, from the cloth to disengage it therefrom; and, fourth,

back again, preparatory to a new engagement with the cloth. Where the above four-motion feed is operated by cams and a spring, the force 'with which the feeding-bar is pressed upon the goods is constant, whatever may be the-resistance which they offer to the feed, and where the cams'or those parts of the feed-bar which rest upon the cams are worn by'use, the amount of engagement of the feeding-foot is liable to vary. With my improved method of operating the feed, the force with which the feedingfoot is caused to press upon the cloth will always be proportionate to the resistance offered to the feed, .while the amount of engagement of the foot with the cloth will not be varied by the wear of the parts which actuate it.

To enable others skilled in-the art to under-' standmy invention, I will proceed to describe the manner in which Ihave carried. it out.

In the accompanying drawings' B is theta ble to which the machine is secured; C, the

metallic frame that carries the operating parts and from which rise the standards that carry the driving-shaft F, one of which is seen atD, Fig. 1.- The shaft F carries a pulley, G,to which may be applied a band from a larger wheel, the crank H, which actuates the feed,

the erankf'l, which drives the necdlc-barK, the needle serving to hold the loop of the and the revolving take-up- L, from. the outer face of which projects the crank-pin j, which, by means of the connecting-rod O, actnates the shuttle.

M is the goose-neck, which sustains the presser-foot and carries the feeding arrangements.

The revolving take-up L, Fig. 1, is composed of two metallic plates, a and I), Fig. 3, which are united together by a rib, N, Fig. 5, the inner plate, I), being secured by a screw, (7, or

otherwiseto the driving-shaft, so that the two plates shall revolve with the shaft. The inner plate, I), is so formed upon the edge, Figs...3

and 5, as to retain thethreadinaslight groove, c,'whieh extends from 1 to 2, and so long as the thread remains in this groove the thread .will continue to .be tightened up; but at the point 2 the groove runs out and the thread then slips oil and becomes instantly slack.

The position of the rib N and groove 0 with respect to the crank which drives the needle, and the crank-pin f,which drives the shuttle, is such that they shall commence to take up the needle-thread as the heel of the shuttle passes through the loop.

The stitch is consequently tightened up. \V l iile the shuttle isupon its return traverse, previous to the drawing up of the thread, the needlehaslcft the cloth, and the stitch is finally tightened rip while the needle is descending again to enter the cloth. So soon, however, as the needle has entered theeloth, its thread, running out of the groove 0, is cast off and becomes entirely slack. It is manifest, as before stated, as the stitehis tightened up while the shuttle is upon its return traverse, that the shuttle-thread must in someway be kept tight, that it may not be drawn through the cloth by the needlethread.

The shuttlc drivcr l is seen in its race in Fig. 2 and detached in Fig. 6. Fig. 7 represents the shuttle, slmttle-driver, and race in section. From one side of the shuttle-driver projects an arm, Q, having a pin, '5, at its extremity, which plays in a slot in the end of an arm, 5,, attached to an upright shaft, S, piv-. otedto the frame-work, and carrying at its upper end a hook, T; This hook is so arranged that when the shuttle has shot through the loop the hook has passed the shuttle-thread as it comes from the cloth to the shuttle, and asthe -shuttle returns, and while the stitch is being tightened up by the revolving take-up, the hook shall carry off the shuttle-thread and keep it tight, Fig. 11. It is evident that the thread which passes over the hook. will be double, one end leading to the seam and the other to the shuttle. lt is therefore necessary that the hook move through but half the space traversed by t1ie sl n1ttlc,. or that the shuttleneedle-threadfro1n being carried forward by the shuttle; but it is manifest that when the needle is driven by a crank it cannot be allowed thus to remain stationary, as it must commence to recede to form the loop before the shuttle advances, and that the loop thus ,left by the needle will be carried along by the shuttle. To remedy this difficulty, and to hold the loop from being carried along bythc shut tle, I place within the shuttle-race a longitudinal rib, h' Fig. 12, which fits in a groove, 1, Fig. 13, in the face of the shuttle. At the point 70? where the necdledescends, this rib is cut away so as to form a shoulder, 3,'against which the needle-thread catches, and bywhich it is prevented from being carried forward by the advancing shuttle.

It now remains to describe the method of operating the feeding bar or foot. fectcd by a direct connection with a vibrating lever, U, which is pivoted to the goose-neck at h. The forward end of this lever is pivoted to a rod, K, which is pivotedat'r to the feedbar m, which is of the form represented in Fig.

8. At 8 the feed-bar is pivoted by a loose joint .to an arm, 2, which is. jointed at a to a block, w. This block is secured to the socket of the presser-foot by ascrew, x, and may be raised or lowered for the purpose of increasing or diminishing the length of the stitch.

The joint at a, between the arm t and the block w, is a tight or friction joint, the arm "being; divided or split and'forced to grasp the pin at' n, on which it turns bythe screw 1), by which means the friction at this point is governed. As the forward end of thelever Uis depressed the feed-bar moves freely'round the joints n'n til the feeding-surface strikes the table or the cloth upon it. The continued descent of the,

lever U now obliges the point .9 to descendyr and the arm t pivots around its friction joint a, and the feeding-surface is driven horizontally across the table, and when the forward end of the lever U is raised the loose joint s permits the feeding-foot to rise out of contact the engagement of the feeding-surface will al- ;ways be proportionate to the resistance offered ;to the motion of thefcloth, and with very light.

Qgoods this pressure will be graduated by the friction produced at the joint a; but wherethe goods are heavy, or where from any cause whatever the feeding is resisted, the foot is pressed with an increased force upon the cloth until it is sufliciently engaged with it to carry it along. v 1

This is'cf- It will be per I am aware that a sewing-machine feed has beenmade having this peculiarity; but such feed has pressed constantly upon the surface ='of the cloth with a given force, and has not had the capability of disengaging, itself entirely therefrom before being retracted, but has scratched back over the surface of the goods.

Any cfficient means of vibrating the lever U may beadopted. In the machine represented in the accompanying drawings I employ the following: W is a shaft, Fig. 4:,which is pivoted in the standards A B and is vibrated a short distance by the crank H, the crank playing in a curved slot, 0, Fig. 4, in an arm projecting .from the shaft W.

its upper extremity an inclined slot, q, in which plays a pin, a, projecting from the lever U, and thus as the shaft F is revolved the lever U is vibrated and the feed is operated.

In the devices heretofore employed to put a constant tension upon the needle-thread by means of pinchers or clamps it has been found ary plate of this tension-regulator, which is attached to an arm, Z, projecting from the framework. From this plate projects a series of short pins, 1, and two longer pins, 3. The movable jaw or plate I is pressed up against the sta= tionary plate by a spring, F, the, tension of which is regulated by a nut, G". The thread from the spool H is passed between the plates E and I, over the pins 1 and beneath the pins 3, thence over the revolving take-up L, then under a guide-roller, K thence throughthe eye to, having a diagonal slit for the entrance of the thread, thence through a similar eye, b, upon the socket of the presser-foot to the needle. The plate I of "the tension-regulator is cut away or bored to admit the pins 1 beneath its surface, that the pressure of the spring F may be thrown upon the thread; 101', in lieu of )ins one of the olates ma 1 have a flan e near 1 7 d as its circumference fitting into a groove in the other and around which the thread is passed.

Operation: The machine being threaded as above, and motion being communicated to the the needle is caused to descend.

From this shaft also projects an arm, D, having atshaft F in the direction of the arrow, Fig. l,

VVhile this descent is taking place, and before its point reaches the cloth, the previously-made stitch is being tightened up by the revolving take-up,

and the shuttle is making its back traverse, the hook T keeping the shuttle-thread tight, as before explained, that this thread may not be drawn through the cloth by the needlethread. As the point of the needle enters the cloth (the stitch being now tightened up) the needle-thread slips off the revolving take-up, and as the needle commencesot-o return, the

shuttle advances and passes through its loop, the thread being-left slack for the purpose. As the needle enters the cloth the feeding-foot rises (the arm on pivoting round the I joint :8) until it strikes the top of the recess in the presser-foot Z, Fig. 9, when, its upward motipn being arrested, the friction-joint at n is forced to yield, and the foot is drawn back. As the point of the needle leaves the goods the feeding-foot is again depressed, its feeding-surface pivoting round the joint 8 until it strikes the cloth, and is snfficiently resisted thereby to cause the friction-joint to yield, when the motion of the foot y will be in theiplane of the table, carrying the cloth alo. with it.

I do not now intend to claim giving to the feeding-instrument of a sewing-machine the fourmotions above described, as this will form the subject of another application foi Letters- Patent; but

What I claim as my invention, and desire to secure by Letters Patent, isj 1. Operating a four-motion feed bymeans of a loose and a friction joint, substantially in the manner and forthe purpose specified.

2. The revolving take-up L, operating as set forth, for the purpose of governing the needlethread, as described.

- 3. The hook T, or any equivalent device for the purpose of keeping the shuttle-thread tight, as described, when used in eombinationwith a needle driven by a crank, as set forth.

4. In combination witha needle driven by acrank, therib h in the shuttle-race, with its notch or. shoulder 3, for the purpose of preventing the loop from being carried forward by the shuttle, as set forth. v

z L. W. LANGDON.

Witnesses:

SAM. CoorER, P. E. TESOHEMACHER. 

